Conventionally, as an example of an electrical connector that electrically connects between a circuit of an internal apparatus and an external circuit, an electrical connector that electrically connects between a circuit for processing an output signal of a fuel pressure sensor 101 shown in FIGS. 10 and 11 and an external circuit is known.
The fuel pressure sensor 101 is attached by screwing to a housing recess 103 of an injector body 102 of an injector that injects fuel into a combustion chamber formed in a cylinder of an internal combustion engine such as a diesel engine, for example, and is for detecting a pressure of fuel injected into the chamber of the engine.
The electrical connector of the fuel pressure sensor 101 has a plurality of terminals 104, a connector case 105 made of a primary molding resin to which a mating connector is fitted, and a connector housing 107 made of a secondary molding resin. The connector housing 107 covers and seals a periphery of a terminal holding portion 106 of the connector case 105 by inserting the terminal holding portion 106 into the secondary molding resin.
The connector case 105 has the terminal holding portion 106 that supports the terminal by embedding intermediate portions of the plurality of terminals 104, and a bottomed cylindrical fitting hood 108 to which the mating connector is fitted.
A fitting recess (cavity) 109 is formed in the fitting hood 108.
An internal connecting portion 111 conductively connected with a terminal electrode 110 of a circuit section of the fuel pressure sensor 101 is provided to each base end of the plurality of terminals 104.
In addition, an external connecting terminal (hereinafter connector terminal) 112 that electrically connects to a mating terminal is disposed on each front end of the plurality of terminals 104.
The connector terminals 112 are projected from a bottom surface of the connector case 105 into the cavity 109 and are exposed therein.
Further, an intermediate portion 113 is provided between the internal connecting portion 111 and the connector terminal 112. The intermediate portion 113 is supported embedding inside the terminal holding portion 106 by an insertion of the primary molding resin.
Furthermore, the circuit section of the fuel pressure sensor 101, the internal connecting portions 111 and the terminal holding portion 106 are supported embedded inside the connector housing 107 by an insertion of the secondary molding resin.
However, when the fuel pressure sensor 101 is disposed in the housing recess 103 of the injector body 102, there is a possibility of liquid such as water or oil entering into the cavity 109 of the electrical connector of the connector case 105.
On the other hand, there is a possibility that small gaps are formed between the connector case 105 and the connector housing 107, and between the connector terminals 112 and the intermediate portions 113 because the primary molding resin forming the connector case 105 and the connector terminals 112 that are the inserted components do not fit tightly.
In such a case, when the liquid enters into the cavity 109, there is a possibility that the liquid may enter into a conductively connected portion of each terminal electrode 110 of the fuel pressure sensor 101 and the internal connecting portion 111 of the plurality of the terminal 104 through gaps between the connector case 105 and the connector housing 107, and between the connector terminals 112 and the intermediate sections 113.
Here, a sealing structure for liquid infiltration to the conductively connected portion from the gaps between the connector case 105 and the connector housing 107, and between the connector terminals 112 and the intermediate sections 113, the following structure is generally known.
That is, a method of sealing peripheries of the connector terminals 112 by pouring a sealant 114 on a bottom surface of the cavity 109, or a method of embedding the terminal 104 by insert-molding in the interior of the terminal holding portion 106 of the connector case 105 by applying the sealant 114 on the surface of the terminal 104 are known (refer to Japanese Patent Publication No. 4565337 and Japanese Patent Application Laid-Open Publication No. H06-084565, for example).
However, in the conventional electrical connector of the fuel pressure sensor 101, if a filling amount of sealant 114 is too large, the electrical connector may not be able to be fitted to the mating connector in a regular fitting position, and if the filling amount is reduced in order to avoid it, there is a problem that the sealing ability is lowered.
Further, an external connector having five terminal fittings, a sealant filling section for filling a sealant, a first holding portion that communicates with the sealant filling section for holding the terminal fittings, and a primary molded body with a second holding portion that communicates with the sealant filling section for holding the terminal fittings is known as an electrical connector (see Japanese Patent Application Laid-Open Publication No. 2013-168212, for example).
In a case of the external connector having such a sealant filling section, since the sealant filling section is open to the outside, a sealant heat resistance (heat resistance reliability, and heat deterioration resistance) during the secondary molding has to be secured.
Further, it is necessary to suppress a decrease in adhesive strength and adhesion of the sealant during heat deterioration during the secondary molding.
Although this is the same in implementation of an integral molding by applying the sealant, when the sealant cannot tolerate the temperature during integral molding, there is a problem that the above structure may not be satisfactory.